1. Field of the Invention
The present invention relates to in-body power supplies having capabilities to compensate for variations in energy transferred to the in-body power supply without communicating with an out-of-body energy source.
2. Background Art
The present invention relates to transcutaneous power supplies. Transcutaneous power supplies are used to supply energy for driving a device implanted within an animal, usually a human. The power supplies typically include an internal unit for receiving energy from an external unit outside the animal. The internal unit receives the energy and uses it to power an in-body device.
The transmission of energy is dependent on a distance and alignment relationship between the external unit and the internal unit. The transmission variations affect the amount of energy received by the internal unit and the ability to properly supply power to the in-body device. The transmission variations should be compensated to ensure sufficient energy is provided to the in-body device. Some systems have attempted to compensate for the transmission variations by providing a means for internal and external unit to communicate with each other. In general, the communication is used to make adjustments to energy transmission levels between the external and internal units. Such systems are problematic in that they are usually complicated and expensive to design and manufacture.